1. Field of the Invention
The invention relates to a lens, more particularly to a light guide lens adapted for guiding light emitted from a light emitting element.
2. Description of the Related Art
in recent years, a light emitting diode (LED) serving as a light source is popularly used in a vehicular light. Light emitted from the LED is primarily guided by a light guide lens to direct outward. A structural design of the light guide lens determines distribution of a light pattern. Referring to FIG. 1, U.S. Pat. No. 7,270,454 B2 discloses a conventional vehicular lamp that includes a light emitting member 11 and a bowl-shaped lens 12. The lens 12 includes a direct light control unit 121, and a reflected light control, unit 122 surrounding the direct light control unit 121. The reflected light control unit 122 has an uneven front surface 123 and an uneven rear surface 124 opposite to the uneven front surface 123 so that the bowl-shaped configuration of the lens 12 is composed of a plurality of rings that are interleaved with each other. The rings have irregular sections and different sectional dimensions. As a result, the light emitted from the light-emitting member 11 toward the direct light control unit 121 tends to directly pass through the direct light control unit 121 and exit therefrom. The light emitted from the light emitting member 11 toward the reflected light control unit 122 tends to be reflected by the rear surface 124 toward the uneven front surface 123. The optical projection pattern produced by this disclosure includes a plurality of annular bright stripes and annular dim stripes interleaved with each other.
Aside from vehicular lamps, other illumination devices, such as lighting devices, signal light devices, decorative lighting devices, advertising light boxes, etc., used either indoor or outdoor also require a light guide lens to complement a light emitting device for emphasizing the profile of the illumination device. In order to meet the diverse needs of customers, a light guide lens with an innovative structure with, a distinct light guide function is provided.